1. Field of the Invention
This invention relates to that class of apparatus which delivers a metered amount of chemicals upon actuation of a cycling fluid level. In particular, the apparatus of this invention is useful for metering a small measured amount of a liquid disinfectant, deodorant, cleaner or the like, into a toilet bowl trap at the conclusion of the flushing cycle.
2. Description of the Prior Art
An apparatus for metering small, measured amounts of chemicals upon actuation by a cycling fluid which would be relatively simple in design, easy to manufacture, having few moving parts and which would be easy to install would find use in both industry and in the consumer products area. Industrial applications would include, for example, the metering into a liquid batch reactor of a small amount of a homogeneous catalyst during each batch cycle of the reactor, or metering into a liquid storage tank a small amount of corrosion inhibitor during each empty-fill cycle. In the consumer products area this apparatus would be useful for supplying a disinfectant, deodorant, cleaner or the like into the toilet bowl trap at the end of the flushing cycle.
Numerous attempts have been made in the prior art to supply chemical disinfectants and the like to toilet bowls, during or after the flushing cycle. Some of these prior art devices employ valves and springs and other mechanical parts which are complex and costly and one such example is shown in U.S. Pat. No. 2,761,151, Ferrando.
A common failing of the prior art resides in the failure to recognize the rather large amount of water which passes through the small refill tube or bypass tube commonly extending between the water inlet and overflow pipes of the flush tank during the flushing operation. The main purpose of this refill tube is is to assure that the bowl trap is refilled with water prior to the next flush. However, in practice, the refill tube supplies significantly more water to the trap than is required to fill it, with the result that any chemical or the like supplied to the trap prior to the closing of the water inlet valve in the tank is generally washed out of the trap and lost down the sewer. Most of the prior art schemes dealing with the problem have completely lost sight of this problem. Examples are U.S. Pat. Nos. 3,084,350, Anderson; 3,001,210, Diehl; and 2,853,715, Ratcliffe. Another problem with prior art devices is that complex design makes them difficult to install. Illustrative of the class are the devices shown in U.S. Pat. Nos. 3,407,412 & 3,444,566 to Spear. These devices require special attachment to the standpipe and bypass tube of a toilet flush tank. Such installation complexities inhibit penetration of such a device into the consumer products market.